The present invention relates to a device for monitoring labor contractions during childbirth. Particularly, the present invention relates to a fiber optic labor contraction sensor adapted to adhere to a females abdomen without the use of a belt or strap. More particularly, the beltless fiber optic labor contraction sensor includes a fiber optic strain sensor that generates an output signal in response to labor contractions and communicates the output signal to a signal transceiver. The signal transceiver is operable to communicate the incidence of labor contractions through radiotelemetry or other wire less communication.
During childbirth, both the strength and frequency of the mother""s labor contractions are monitored. To monitor labor contractions, medical personnel typically utilize force-type strain gauges held against the mother""s abdomen by an elastic belt placed around the mother""s waist. In use, such monitors are, however, bulky and extremely uncomfortable. Further, conventional monitors are generally highly cumbersome and fail to provide the mother with mobility outside the bed during the birthing process. More specifically, a mother is normally restricted to the bed during childbirth and if the mother needs to exit the bed and move about, she must first remove the attached monitor. Another limitation of presently employed monitoring devices is the limited range of mobility afforded the mother due to the signal cables connecting the monitoring device to a contraction recording system.
The problems described above are not intended to be exhaustive but are merely a few of those tending to reduce the effectiveness of the monitors presently used to detect labor contractions. These problems demonstrate that presently used monitors are not satisfactory and illustrate further the need for an improved device for detecting labor contractions.
In accordance with the present invention, a labor contraction sensing device includes a fiber optic strain sensor that is adhered to the mother""s abdomen for detecting the strength and frequency of labor contractions during childbirth. The fiber optic strain sensor is in signal communication with a signal transceiver having a signal transmitter that is in wire less communication with a standard contraction recording device or other monitoring equipment.
Therefore, in accordance with a general embodiment of the present invention, there is provided a fiber optic strain sensor including at least one fiber optic cable having first and second ends. A light source is located at one end of the fiber optic cable for transmitting a light beam through the fiber optic cable to the opposite end of the fiber optic cable. A light detector is located at the opposite end of the cable for detecting fluctuations in the transmitted fiber optic light beam. In operation, any external forces acting against the fiber optic cable, such as the tightening of the mother""s abdomen due to the onset of a contraction, results in changes in the optical signal of the transmitted light beam. These fluctuations are detected by the light detector and an appropriate output signal is generated by optical signal processing electronics. The sensor output signal is communicated to a signal transceiver, which includes a signal receiver and transmitter.
In a further embodiment, the signal transmitter is a radio transmitter. Utilizing a radio transmitter as the signal transmitter provides the user with wire less communication between the labor contraction sensing device and a standard contraction recording system. Additionally, the fiber optic strain sensor is specially designed to be adhered to the mother""s abdomen without the use of a belt. Specifically, the fiber optic strain sensor includes an adhesive surface or is placed within an adhesive cover or jacket that allows the fiber optic strain sensor to be conveniently and comfortably adhered to the abdomen of the mother. The beltless design together with wireless communication provides a labor contraction sensing device that offers increased mobility to the expecting mother relative to existing contraction sensing devices.